8 



coal measures of France. 1 I have not in my own collections 

 any specimens proving this collocation of parts, but give it 

 here on the authority of the French palseo-botanist. The 

 structure of the stem of Dolerophyllum does not appear to be 

 known, but its affinities would seem to be Cycadean, and the 

 organs of fructification above described have some re- 

 semblance to the remarkable Carpolithes horridus of our Cre- 

 taceous of the North-west. 2 The species collected by Mr. 

 Lacoe so closely resembles D. Gospperti of Saporta, that I 

 hesitate to give it a specific name. It may, however, be 

 distinguished by its longer marginal rays and larger pits on 

 the disk, and may be provisionally named D. Pennsyl- 

 vanicum. 



TYLODENDRON, Weiss. 



A very important class of fossils in connection with the 

 subject of this paper is that included in the genus Tylodendron 

 of Weiss, which are more characteristic of the upper than 

 the lower members of the later Palaeozoic. They are, how- 

 ever, closely allied to some of the forms included in the 

 genus Knorria, which goes back to the Devonian. These 

 stems are characterised by elongated ridges spirally 

 arranged, and with a slight groove at one end. Some speci" 

 mens also show distinct swellings or nodes of larger scars 

 as if giving origin to whorls of smaller branches. They are 

 most frequently sandstone casts , and the surface markings 

 are not those of a true exterior surface, but of an inner cylin- 

 der showing the points of exit of bundles of fibres or ves- 

 sels. These stems have received several names. They 

 constitute the genera Schizodendron and Angiodendron of 

 Eichwald, and the Lepidodendron elongatum of Brongniart is 

 is apparently of this nature. It is difficult to distinguish them 

 into good species, and the T. speciosum of Weiss covers most 

 of the forms. Weiss has described the structure of the 

 stem as consisting of a cellular pith surrounded with a 



1 Evolution des Plantes, Phsenogames, p. 75. 



2 Trans. B. Socy. of Canada, Vol. I, p. 21, PI, I., Fig. 3. 



